I'm running a dual boot Ubuntu 12.04/Windows 7 machine. When I set up the system, I made the mistake of not setting up separate partitions. I also made the mistake of not defragmenting the HDD before I installed Ubuntu. This probably has something to do with this error I'm getting, but I'm not really sure how to fix it at this point.

I did the commands you said, and it's still coming up with the low disk space error. I can't unmount /dev/loop0. What is it? I don't have any ISO files mounted that I'm aware of.
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ElliottNov 6 '13 at 23:25